Cerebral stroke is a disease in which a cerebral tissue damage is caused by a sudden blood vessle rupture or by a blood circulation disturbance arising from vascular obstruction in brain. Ischemic cerebral stroke means necrosis of local cerebral tissues including neurocytes, neurogliocytes, and blood vessel due to deficient in blood supply. The fundamental cause of the ischemic cerebral stroke is that the extracranial or intracranial arteries leading to the brain have occlusive lesions and fail to achieve prompt and adequate collateral circulation so that the metabolism requirement of the local cerebral tissues cannot be met by the available blood supply. The incidence of ischemic cerebral stroke is higher than that of hemorrhagic cerebral stroke and accounts for 60%-70% of all cerebral stroke cases. The occlusion and stenosis in internal carotid and vertebral arteries may cause ischemic cerebral stroke in people older than 40 in a higher frequency in males than in females. Some severe cases result in death.
The sequelae of ischemic cerebral stroke means the symptoms of hemiplegia, speech disorder, or facial paralysis and the like occurred after the ischemic cerebral stroke, collectively referred to as sequelae of ischemic cerebral stroke. Mainly, these include the following symptoms: semiplegia (hemiplegia), hemi-limb disabilities, numbness of limbs, hemianopsia, aphasia, or crossed hemiplegia, contralateral sensory disturbance, e external ophthalmoplegia, nystagmus, dyslalia, speech disorder, memory deterioration, facial paralysis, dysphagia, choking on food and drink, dystaxia, dizzy and headache, and the like.
Reckoning on the survey data obtained 20 years ago, there are about 2 million of new cerebral stroke cases every year in China, more than 150 million persons died from cerebral stroke every year, and there are about 600-700 million survived from cerebral stroke. Among the survival patients, about 75%-80% would have different levels of sequelae, with over 40% of severe disability. About ¼ to ⅓ of them may relapse within 2 to 5 years. With the improvement in living standards and the change of the life style in recent years, the population incidence of cerebral stroke is still rising in China. In particular, because of the improvement of medical conditions and the advancement of clinical technology, the mortality rate of stroke significantly declined while, however, leading to a great increase in the morbidity of the sequelae of cerebral stroke, which causes a greater disease burden. The cerebral stroke has become a leading disease that jeopardizes the health of middle aged and elderly people in China.
At present, butylphthalide (NBP) is a drug approved for the treatment of sequelae of ischemic cerebral stroke. The sodium chloride injection of butylphthalide (which has the principal component of butylphthalide with a chemical name of d1-3-n-butylphthalide (called as butylphthalide or NBP for short)) is used for improving neurological function deficits in a patient with acute ischemic cerebral stroke. The drug is administered through an intravenous drip within 48 hours from the onset of the disease, twice per day, each 25 mg (100 ml) over a period of less than 50 minutes with a time interval of not less than 6 hours between two administrations during a treatment course of 14 days. Since a PVC infusion device has a significant absorption effect on butylphthalide, a PE infusion device can only be used for the infusion of the butylphthalide product. There is no research data about the efficacy or safety of the drug administered 48 hours after the onset of the disease. The butylphthalide soft capsule has an indication of mild or moderate acute ischemic cerebral stroke. In a specification of 0.1 g, the drug is administered orally under fasting, two capsules (0.2 g) every time, four times every day during a treatment course of 10-12 days, or as recommended by the doctor. Unwanted effects include mild transaminase elevation, which can be normalized after drug withdrawal according to some follow-up cases. Nausea, abdominal discomfort, rash, psychiatric symptoms and the like happen occasionally.
In addition, aspirin is also used to treat sequelae of ischemic cerebral stroke. Aspirin has a generic name of acetylsalicylic acid, and is an antipyretic analgesics with a long history since its discovery in 1899. It has been used for treating cold, fever, headache, toothache, arthralgia, and rheumatism, and is capable of inhibiting platelet aggregation, thereby preventing and treating ischemic cardiopathy, angina, cardiopulmonary infarction, and cerebral thrombosis. However, aspirin has no significant efficacy on the treatment of sequelae of ischemic cerebral stoke, but has multiple adverse effects. Accordingly, when aspirin is used to treat various diseases, one should keep close watch over its adverse effects.
Therefore, there still is a great need now to develop a new medicinal substance for treating sequelae of ischemic cerebral stroke in the current society.